It's been a riveting month at Guantánamo. First was the sad spectacle of the “arraignment” of alleged 9/11 conspirators — in a courtroom expressly designed to suppress their statements about brutal torture in CIA custody, and in a system expressly fashioned to permit their execution on the basis of evidence extracted through that torture. The embarrassing proceedings were rushed forward in a last-ditch Bush administration effort to turn Guantánamo to its political advantage, but, as usual, it was the administration that endured ridicule for the very public collapse of its “full and fair” military commission system.

And then, on Thursday, the hammer truly fell with the Supreme Court’s final rebuke to the legal and moral disaster of the Guantánamo detention regime. We shouldn’t need a Supreme Court decision to remind us that executive detention without judicial review violates our most fundamental constitutional values — but we did, and the Court delivered, and we should be proud of the Court and of our system and of all the lawyers who worked for six years to make yesterday’s landmark decision possible.

We have had moments like this in the last four years, only to see defeat snatched from the jaws of victory. This was the third Supreme Court repudiation of Guantánamo “justice,” but after each of the first two victories — Rasul in 2004, and Hamdan in 2006 — the Bush administration and a compliant Republican Congress effectively reversed the Court’s decisions with ill-advised (and, we can now say, unconstitutional) legislation — only to be reversed again by the Court. Could it happen again? There’s a sense, I think, that this constitutional whack-a-mole may be over, and that the administration may have permanently overplayed its hand.

So why is my own celebration muted? I can’t stop thinking about a scene I witnessed in Guantánamo this past April during military commission proceedings against Salim Ahmed Hamdan, whose challenge to the legality of President Bush’s first military commission system resulted in a resounding Supreme Court defeat for the Bush Administration. The military judge saluted Hamdan, telling him that he should be proud to have taken on the government and won. But Hamdan pointed out that his victory had been hollow — that his reward was to face trial once again in unfair and illegal proceeding.

Hamdan the case is already being studied by law students, but Hamdan the man is sitting alone, as you read this, in a windowless cell. He and the other men still detained are closer than ever to having their detention reviewed by an impartial decision maker. But these cases could have been in court many years ago had the administration not fought so tirelessly to evade the rule of law.

Earlier this week I had another painful reminder of the consequences of the administration’s abandonment of the rule of law. I was in Germany visiting my client, Khaled El-Masri, perhaps the best-known victim of the CIA’s so-called extraordinary rendition program. El-Masri, an entirely innocent man, was kidnapped by the CIA, chained to the floor of a plane, injected with drugs, transported to a secret prison in Afghanistan, interrogated under torture, and only released months after the CIA realized it had abducted the wrong man. Like the vast majority of Guantánamo detainees, he was never charged with a crime. Like the Guantánamo detainees, he was transported to a place where, in the administration’s view, no law applied. We may never know how many of the Guantánamo detainees were innocent, like El-Masri. But we know without doubt that when the protections of our Constitution and international law are stripped away, such tragic mistakes go uncorrected. There’s reason to hope that the Boumediene decision will prevent the needless suffering of the next Khaled El-Masri. And that’s certainly worth celebrating.